My aim to teach you about patent law; FYI this is a breach of your NDA. Here is some supplemental information about the law, and why you shouldn't be disclosing any information http://www.aipla.org/about/iplaw/Pages/default.aspx. I'm not saying that someone is going to go after your profesor's intelectual property because this is a community where people learn together. Answering any question entitles the answerer a part of the property because its their idea. Ask your professor. It is probably more worrisome to them by not being asked questions. Every chemist eventually encounters obstacles in synthesis. 1) Is it freshly prepared? You should know how to determine purity to figure out how much to add. 2) THF is easier to work with than Et2O. 3) You are doing a mole calculation before the experiment. NH4Cl is a milder acid. 4) I would look into transition metal catalyzed grinard reactions e.g. gilman etc
My aim to teach you about patent law; FYI this is a breach of your NDA. Here is some supplemental information about the law, and why you shouldn't be disclosing any information http://www.aipla.org/about/iplaw/Pages/default.aspx. I'm not saying that someone is going to go after your profesor's intelectual property because this is a community where people learn together. Answering any question entitles the answerer a part of the property because its their idea. Ask your professor. It is probably more worrisome to them by not being asked questions. Every chemist eventually encounters obstacles in synthesis. 1) Is it freshly prepared? You should know how to determine purity to figure out how much to add. 2) THF is easier to work with than Et2O. 3) You are doing a mole calculation before the experiment. NH4Cl is a milder acid. 4) I would look into transition metal catalyzed grinard reactions e.g. gilman etc
Okay. 1) titrate a solution and measure the pH with an electrode. what equation do you use? 2) Yes, the pKa of RR'=NMgBr is 33 NH3 is 12. Excess is fine unless there is a acid sensitive functional group, and use NH4Cl(aq<in excess). Can you think of a way of how to check? The answer lies within the intrinsic properties of the chemicals. 3) don't buy copper(I). Prepare it.
Okay. 1) titrate a solution and measure the pH with an electrode. what equation do you use? 2) Yes, the pKa of RR'=NMgBr is 33 NH3 is 12. Excess is fine unless there is a acid sensitive functional group, and use NH4Cl(aq
Actually I don't have a supervisor at the moment, I am at a Uni but at a privately funded research start up company. I could ask other professors but I feel a little awkward, especially being new. My actual boss is a mechanical engineer, and doesn't know hardly anything about chemistry (moles dig holes in the ground!).
1) Yes the grignard is freshly prepared. I'm not sure how to determine the purity of my grignard sorry. Could you steer me in the right direction? 3) So for the mole calculation on how much acid to use, do I assume that 100% of the nitrile changes into the intermediate imine? I'll definitely be adding an excess of acid that way, i'm not sure it's a good idea. Is there another way to check my acid workup is complete? 4) This suggestion was extremely helpful thank you!!!! I've found an article about copper(I) catalysts which greatly speed up the reaction, from 24 hours reflux 10% yield to 2 hours reflux 99% yield in some cases!
Actually I don't have a supervisor at the moment, I am at a Uni but at a privately funded research start up company. I could ask other professors but I feel a little awkward, especially being new. My actual boss is a mechanical engineer, and doesn't know hardly anything about chemistry (moles dig holes in the ground!).
1) Yes the grignard is freshly prepared. I'm not sure how to determine the purity of my grignard sorry. Could you steer me in the right direction? 3) So for the mole calculation on how much acid to use, do I assume that 100% of the nitrile changes into the intermediate imine? I'll definitely be adding an excess of acid that way, i'm not sure it's a good idea. Is there another way to check my acid workup is complete? 4) This suggestion was extremely helpful thank you!!!! I've found an article about copper(I) catalysts which greatly speed up the reaction, from 24 hours reflux 10% yield to 2 hours reflux 99% yield in some cases!
Sorry for making a new account, forgot my password to this site and have a new email.
I'm back on the task of adding my grignard to a nitrile, and it is working, but in incredibly low yield.
My nitrile has a CH2 group next to the CN, and I read on here and in a journal article that the grignard can can react to form RH, deprotonating alpha hydrogens from the nitrile, which leads to less formation of desired imine intermediate, and formation of trimers etc.
I've read that this reaction is often carried out at 0 deg C, what is the point of this if will be refluxed later anyway? Is there a reason?
Will refluxing make more of the trimer and less of the desired imine? Or it doesn't matter?
I'm using copper(I) iodide as catalyst. 1:1 grignard to nitrile. Should I be adding 2:1 grignard to nitrile?
Sorry for making a new account, forgot my password to this site and have a new email.
I'm back on the task of adding my grignard to a nitrile, and it is working, but in incredibly low yield.
My nitrile has a CH2 group next to the CN, and I read on here and in a journal article that the grignard can can react to form RH, deprotonating alpha hydrogens from the nitrile, which leads to less formation of desired imine intermediate, and formation of trimers etc.
I've read that this reaction is often carried out at 0 deg C, what is the point of this if will be refluxed later anyway? Is there a reason?
Will refluxing make more of the trimer and less of the desired imine? Or it doesn't matter?
I'm using copper(I) iodide as catalyst. 1:1 grignard to nitrile. Should I be adding 2:1 grignard to nitrile?
Are you exposing the CuI to oxygen? do this reaction under inert aphmosphere, and also your CuI may be bad because of oxygen seeping into it; preparation from fresh Cu(II) is not that complicated of a procedure. If you're refluxing, 0°C and dropwise at first to lessen the enthalpy change because grignard neutralizing will create alot of heat speeding up side reactions. If it still not working just go with another reaction sequence. For example, http://www.organic-chemistry.org/synthesis/N1H/reductionsnitriles.shtm or hydrate the thing to the COOH and then add oxalyl chloride(easy to distill) and DMF as a catalyst to convert to acid chloride etc. Go the the uni and set up a scifinder account and research. there are lots of ways to convert your starting material into what you want. Better results than bumping your head into a wall trying the same procedure over and over
Are you exposing the CuI to oxygen? do this reaction under inert aphmosphere, and also your CuI may be bad because of oxygen seeping into it; preparation from fresh Cu(II) is not that complicated of a procedure. If you're refluxing, 0°C and dropwise at first to lessen the enthalpy change because grignard neutralizing will create alot of heat speeding up side reactions. If it still not working just go with another reaction sequence. For example, http://www.organic-chemistry.org/synthesis/N1H/reductionsnitriles.shtm or hydrate the thing to the COOH and then add oxalyl chloride(easy to distill) and DMF as a catalyst to convert to acid chloride etc. Go the the uni and set up a scifinder account and research. there are lots of ways to convert your starting material into what you want. Better results than bumping your head into a wall trying the same procedure over and over
1) Is it freshly prepared? You should know how to determine purity to figure out how much to add.
2) THF is easier to work with than Et2O.
3) You are doing a mole calculation before the experiment. NH4Cl is a milder acid.
4) I would look into transition metal catalyzed grinard reactions e.g. gilman etc
1) Is it freshly prepared? You should know how to determine purity to figure out how much to add.
2) THF is easier to work with than Et2O.
3) You are doing a mole calculation before the experiment. NH4Cl is a milder acid.
4) I would look into transition metal catalyzed grinard reactions e.g. gilman etc
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Actually I don't have a supervisor at the moment, I am at a Uni but at a privately funded research start up company. I could ask other professors but I feel a little awkward, especially being new. My actual boss is a mechanical engineer, and doesn't know hardly anything about chemistry (moles dig holes in the ground!).
1) Yes the grignard is freshly prepared. I'm not sure how to determine the purity of my grignard sorry. Could you steer me in the right direction?
3) So for the mole calculation on how much acid to use, do I assume that 100% of the nitrile changes into the intermediate imine? I'll definitely be adding an excess of acid that way, i'm not sure it's a good idea. Is there another way to check my acid workup is complete?
4) This suggestion was extremely helpful thank you!!!! I've found an article about copper(I) catalysts which greatly speed up the reaction, from 24 hours reflux 10% yield to 2 hours reflux 99% yield in some cases!
Actually I don't have a supervisor at the moment, I am at a Uni but at a privately funded research start up company. I could ask other professors but I feel a little awkward, especially being new. My actual boss is a mechanical engineer, and doesn't know hardly anything about chemistry (moles dig holes in the ground!).
1) Yes the grignard is freshly prepared. I'm not sure how to determine the purity of my grignard sorry. Could you steer me in the right direction?
3) So for the mole calculation on how much acid to use, do I assume that 100% of the nitrile changes into the intermediate imine? I'll definitely be adding an excess of acid that way, i'm not sure it's a good idea. Is there another way to check my acid workup is complete?
4) This suggestion was extremely helpful thank you!!!! I've found an article about copper(I) catalysts which greatly speed up the reaction, from 24 hours reflux 10% yield to 2 hours reflux 99% yield in some cases!
More
VOTE
I'm back on the task of adding my grignard to a nitrile, and it is working, but in incredibly low yield.
My nitrile has a CH2 group next to the CN, and I read on here and in a journal article that the grignard can can react to form RH, deprotonating alpha hydrogens from the nitrile, which leads to less formation of desired imine intermediate, and formation of trimers etc.
I've read that this reaction is often carried out at 0 deg C, what is the point of this if will be refluxed later anyway? Is there a reason?
Will refluxing make more of the trimer and less of the desired imine? Or it doesn't matter?
I'm using copper(I) iodide as catalyst. 1:1 grignard to nitrile. Should I be adding 2:1 grignard to nitrile?
Thanks!!
I'm back on the task of adding my grignard to a nitrile, and it is working, but in incredibly low yield.
My nitrile has a CH2 group next to the CN, and I read on here and in a journal article that the grignard can can react to form RH, deprotonating alpha hydrogens from the nitrile, which leads to less formation of desired imine intermediate, and formation of trimers etc.
I've read that this reaction is often carried out at 0 deg C, what is the point of this if will be refluxed later anyway? Is there a reason?
Will refluxing make more of the trimer and less of the desired imine? Or it doesn't matter?
I'm using copper(I) iodide as catalyst. 1:1 grignard to nitrile. Should I be adding 2:1 grignard to nitrile?
Thanks!!
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